On Sat, Oct 29, 2011 at 03:44:46PM -0700, Nick Prince wrote:
> [NP]
> > > Maybe you are thinking of Tegmark level 1 or level 2 type multiverses
> > > here, in which case I agree.  What I was doing in my analysis was
> > > thinking about QM type 3 multiverses only. Let's pretend that these
> > > are the only variety for the moment, then my analysis does indicate
> > > that cul de sacs arise only if the unitary development during
> > > interactions follow the ideal measurement prescription.  You can see
> > > this because in the times between the action of operator Mdev and Mc
> > > the cat is alive in both branches but destined to die in one of them.
> >
> >[RS]
> Why do you think there are conscious moments during the unitary
> > evolution between Mdev and Mc? Surely the evolution between successive
> > observer moments must be nonunitary. Unitary evolution is essentially
> > unobservable.
> >
> [NP]
> Perhaps I should have said between Msg and Mdev (although the argument
> is still similar)  that U(t) |moves up>= |moves up> over the period t.
> i.e. once the electron interacted with the SG device it took a while
> to reach the detector but the state of the system did not change in an
> important way.  I know that perhaps I should have put some position
> representation in there but I don't think that's what your getting
> at?
> I'm assuming that there is no collapse of the wavefunction so my
> experiences are all experienced because states evolve unitarily. I
> understand that the unitary operator is not an observable operator but
> I can observe the consequences of its action on a system because I
> measure observables that give different eigenvalues each time I look
> (experience things - my experiencing is a form of measurement).  Are
> you saying that during an OM there is no change i.e. it is a static
> picture? Are you thinking that unitary evolution goes on in between
> the static pictures? Surely the t in the exponential means that the
> system evolves over that t.  As a ist person I can observe things
> changing over this t. Can you help me to see if I am making an error
> of thinking?
> Nick

The question is - when did the cat become aware of which way the
electron was spinning as it left the Stern-Gerlach apparatus? I would
say it was when it discovered the vial didn't smash, and it was still alive.

The other question, from the DD perspective, is when did the sphere of
differentiation propagate from the SG apparatus to include the cat.



Prof Russell Standish                  Phone 0425 253119 (mobile)
Principal, High Performance Coders
Visiting Professor of Mathematics      hpco...@hpcoders.com.au
University of New South Wales          http://www.hpcoders.com.au

You received this message because you are subscribed to the Google Groups 
"Everything List" group.
To post to this group, send email to everything-list@googlegroups.com.
To unsubscribe from this group, send email to 
For more options, visit this group at 

Reply via email to